1. Technical Field of the Invention
This invention relates generally to portable communication devices and, more particularly, to portable radio telephones which utilize a hinged flip portion to allow access to the keypad of the phone.
2. Description of Related Art
Telephones having rotary or push button dial mechanisms and other buttons integral to the handset portion have become commonplace in landline subscriber stations. This arrangement offers the telephone user the convenience of bringing the user interface mechanism and control buttons close to the user.
Cellular communication devices, and cordless telephone sets, provide user mobility not offered by conventional landline telephones. The lack of the cord and the small size of the portable cellular communication device enables the user to simultaneously carry and use the unit. Such portability, however, typically requires additional action by the user to activate the telephone. For example, a landline phone is merely activated by lifting a handset off a phone base. Portable phones, including cellular and cordless phones, typically include a dedicated push-button switch which must be depressed to activate the phone. Thus, the user must depress a dedicated push-button switch before dialing a phone number or to answering a call. On other phones, and more commonly on cellular phones, the depression of any key on the keypad, or at least of any numerical key on the keypad, serves to activate the phone when a call is being received. In both cases, however, a user must hold the phone, examine the selection of keys, depress a key, and then move the phone into a communication position to activate the phone.
Some portable phone manufacturers, and especially phone cellular manufacturers, utilize what is commonly known as the "flip phone". The flip phone includes a hinged portion which acts as a cover for the cellular phone keypad whenever the hinged portion is in a closed position. To use a flip phone, a user usually must rotate the hinged portion from a closed position to a predetermined open position before receiving a call. Additionally, the user must depress a specified push-button switch or, at least, any key on the keypad to activate the phone. Thus, for a flip phone, a user must engage in a sequence of actions while the call is being received, to activate the phone, to actually take the call. The requisite switch action to activate the phone and connect the user to the call being received is substantial as compared to conventional landline phones. With landline phones, the phone is activated simply by lifting the handset off a dedicated switch. Lifting the handset activates the landline phone and connects the user to the caller. It is desirable, therefore, to simplify the user steps for activating a flip phone either whenever a call is being received or when the user desires to place a call. It would also be desirable to utilize simple and reliable circuitry in accomplishing this goal.